package org.hnsd.train.pattern.observer;

/**
 * @author youqd
 * @tag.date 2023-11-07 23:04
 **/
public class Client {
    public static void main(String[] args) {
        Subject subject = new ConcreteSubject();
        Observer observer = new ConcreteObserver();
        subject.attach(observer);
        subject.notifyObserver();
    }
}
//
//eventtop ------------- topic(event)----> (a ,b ,c) key ,type
//
//customer ------
//event --- A
//      --- B
//      --- C
//
//A --- Oberser --- a
//B --- Oberser --- b
//C --- Oberser --- c
